2011-08-09_REVISION - M1981185 (52)

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Mine Rock Geochemical Analysis Exhibit U — Attachment U -6 • Acid -Base Accounting: A representative sample was ground to 2 mesh and analyzed for pH (1:1 rock: de- ionized water extract), Total Sulfur (high - temperature furnace combustion) a CaCO3 (digestion with hot acid, titration with NaOH). Acid Potential was calculated by multiplying Total Sulfur x 31.25 (Sobek et. al., 1978) and Neutralization Potential calculated from the amount of acid that was neutralized. Acid -Base Potential is calculated from subtracting Acid Potential from Neutralization Potential; and • Synthetic Precipitate Leachate Procedure (SPLP): A representative sample was ground to 21/2 mesh and analyzed in accordance with SW -846 Method 1312 (USEPA, 2007). The leachate was analyzed for metals and trace metals utilizing USEPA Methods 200.7 (Inductively Coupled Plasma- Atomic Emission Spectrometry) and 200.8 (Inductively Coupled Plasma — Mass Spectrometry). The metals analyzed are listed in Exhibit U, Attachment 7, Table U -3. 2.0 Analytical Results 2.1 Whole Rock Analysis Whole Rock Analytical results are presented in Exhibit U, Attachment 7, Table U -1, and analytical reports are appended to this report. Major elements (reported as oxides) and trace elements (reported as elemental values) comprise 96.9% of the sample. Within the Acid -Base Accounting (Exhibit U, Attachment 7, Table U -2) CaCO3 is reported as 6.2 %, of which 3.1% will be CaCO3 indicating that the majority of the volatile component is CO3' rather than H2O. SiO2 and Al2O3 dominate the oxides, indicating that the sample is felsic in nature, with Ca and K the dominate alkali and alkaline earth metals. Sulfur concentrations as determined by XRF (1.10 %, Exhibit U, Attachment 7, Table U -1) is similar to that determined by combustion (1.75 %, Exhibit U, Attachment 7, Table U -2). Zinc was the dominate trace metal (684 ppm). 2.2 Acid -Base Accounting Acid -Base Accounting results are presented in Exhibit U, Attachment 7, Table U -2, and analytical reports are appended to this report. The pH of the mine rock was 7.5. The Neutralizing Potential (62.2 kg /ton) was greater than the Acid Potential (54.6 kg /ton) producing a positive Acid -Base Potential (7.55 kg/ton). 2.3 Synthetic Precipitate Leachate Procedure SPLP results are presented in Exhibit U, Attachment 7, Table U -3, and analytical reports are appended to this report. Analytical results were compared to both groundwater and surface water basic standards. For surface water, the chronic standard was used as it was assumed that the leaching of any rock will occur over long periods of time rather than an immediate release. Although the hardness value of the mine rock, based on calculations using the calcium and magnesium concentrations was greater than 400 mg/L as CaCO3, hardness based standards for Wildcat Mining Corporation May Day Idaho Mine Complex — 112d Permit Application Revised August 2011 Exhibit U — Attachment U -6 Page 2 of 3